Rare earth elements (REEs) are essential components of current and emerging 21st century technologies. Recent concern about future supplies of all the REEs now has narrowed chiefly to the heavy rare earth elements (HREEs). Essentially, all of the world's HREEs currently are sourced from the south China ion-adsorption clay deposits. The ability of those deposits to maintain and increase production is uncertain, particularly in light of environmental degradation associated with some mining and extraction operations in the region.
As such, identification and development of processes for improved extraction and recovery of REEs is desired in order to exploit deposits in other parts of the world.